import org.scalatest.FunSuite

 class MySuite extends FunSuite {

   test("addition") {
     val sum = 1 + 1
     assert(sum === 2)
     assert(sum + 2 === 4)
   }

   test("subtraction") {
     val diff = 4 - 1
     assert(diff === 3)
     assert(diff - 2 === 1)
   }
 }
 

“test” is a method, defined in FunSuite, which will be invoked by the primary constructor of MySuite. You specify the name of the test as a string between the parentheses, and the test code itself between curly braces. The test code is a function passed as a by-name parameter to test, which registers it for later execution. One benefit of FunSuite compared to Suite is you need not name all your tests starting with “test.” In addition, you can more easily give long names to your tests, because you need not encode them in camel case, as you must do with test methods.

A FunSuite's lifecycle has two phases: the registration phase and the ready phase. It starts in registration phase and enters ready phase the first time run is called on it. It then remains in ready phase for the remainder of its lifetime.

Tests can only be registered with the test method while the FunSuite is in its registration phase. Any attempt to register a test after the FunSuite has entered its ready phase, i.e., after run has been invoked on the FunSuite, will be met with a thrown TestRegistrationClosedException. The recommended style of using FunSuite is to register tests during object construction as is done in all the examples shown here. If you keep to the recommended style, you should never see a TestRegistrationClosedException.

Shared fixtures

A test fixture is objects or other artifacts (such as files, sockets, database connections, etc.) used by tests to do their work. You can use fixtures in FunSuites with the same approaches suggested for Suite in its documentation. The same text that appears in the test fixture section of Suite's documentation is repeated here, with examples changed from Suite to FunSuite.

If a fixture is used by only one test, then the definitions of the fixture objects can be local to the test function, such as the objects assigned to sum and diff in the previous MySuite examples. If multiple tests need to share a fixture, the best approach is to assign them to instance variables. Here's a (very contrived) example, in which the object assigned to shared is used by multiple test functions:

 import org.scalatest.FunSuite

 class MySuite extends FunSuite {

   // Sharing immutable fixture objects via instance variables
   val shared = 5

   test("addition") {
     val sum = 2 + 3
     assert(sum === shared)
   }

   test("subtraction") {
     val diff = 7 - 2
     assert(diff === shared)
   }
 }
 

In some cases, however, shared mutable fixture objects may be changed by tests such that they need to be recreated or reinitialized before each test. Shared resources such as files or database connections may also need to be created and initialized before, and cleaned up after, each test. JUnit offers methods setUp and tearDown for this purpose. In ScalaTest, you can use the BeforeAndAfterEach trait, which will be described later, to implement an approach similar to JUnit's setUp and tearDown, however, this approach often involves reassigning vars between tests. Before going that route, you should consider some approaches that avoid vars. One approach is to write one or more create-fixture methods that return a new instance of a needed object (or a tuple or case class holding new instances of multiple objects) each time it is called. You can then call a create-fixture method at the beginning of each test that needs the fixture, storing the fixture object or objects in local variables. Here's an example:

 import org.scalatest.FunSuite
 import scala.collection.mutable.ListBuffer

 class MySuite extends FunSuite {

   // create objects needed by tests and return as a tuple
   def createFixture = (
     new StringBuilder("ScalaTest is "),
     new ListBuffer[String]
   )

   test("easy") {
     val (builder, lbuf) = createFixture
     builder.append("easy!")
     assert(builder.toString === "ScalaTest is easy!")
     assert(lbuf.isEmpty)
     lbuf += "sweet"
   }

   test("fun") {
     val (builder, lbuf) = createFixture
     builder.append("fun!")
     assert(builder.toString === "ScalaTest is fun!")
     assert(lbuf.isEmpty)
   }
 }
 

If different tests in the same FunSuite require different fixtures, you can create multiple create-fixture methods and call the method (or methods) needed by each test at the begining of the test. If every test requires the same set of mutable fixture objects, one other approach you can take is make them simply vals and mix in trait OneInstancePerTest. If you mix in OneInstancePerTest, each test will be run in its own instance of the FunSuite, similar to the way JUnit tests are executed.

Although the create-fixture and OneInstancePerTest approaches take care of setting up a fixture before each test, they don't address the problem of cleaning up a fixture after the test completes. In this situation, one option is to mix in the BeforeAndAfterEach trait. BeforeAndAfterEach's beforeEach method will be run before, and its afterEach method after, each test (like JUnit's setUp and tearDown methods, respectively). For example, you could create a temporary file before each test, and delete it afterwords, like this:

 import org.scalatest.FunSuite
 import org.scalatest.BeforeAndAfterEach
 import java.io.FileReader
 import java.io.FileWriter
 import java.io.File

 class MySuite extends FunSuite with BeforeAndAfterEach {

   private val FileName = "TempFile.txt"
   private var reader: FileReader = _

   // Set up the temp file needed by the test
   override def beforeEach() {
     val writer = new FileWriter(FileName)
     try {
       writer.write("Hello, test!")
     }
     finally {
       writer.close()
     }

     // Create the reader needed by the test
     reader = new FileReader(FileName)
   }

   // Close and delete the temp file
   override def afterEach() {
     reader.close()
     val file = new File(FileName)
     file.delete()
   }

   test("reading from the temp file") {
     var builder = new StringBuilder
     var c = reader.read()
     while (c != -1) {
       builder.append(c.toChar)
       c = reader.read()
     }
     assert(builder.toString === "Hello, test!")
   }

   test("first char of the temp file") {
     assert(reader.read() === 'H')
   }
 
   test("without a fixture") {
     assert(1 + 1 === 2)
   }
 }
 

In this example, the instance variable reader is a var, so it can be reinitialized between tests by the beforeEach method.

Although the BeforeAndAfterEach approach should be familiar to the users of most test other frameworks, ScalaTest provides another alternative that also allows you to perform cleanup after each test: overriding withFixture(NoArgTest). To execute each test, Suite's implementation of the runTest method wraps an invocation of the appropriate test method in a no-arg function. runTest passes that test function to the withFixture(NoArgTest) method, which is responsible for actually running the test by invoking the function. Suite's implementation of withFixture(NoArgTest) simply invokes the function, like this:

 // Default implementation
 protected def withFixture(test: NoArgTest) {
   test()
 }
 

The withFixture(NoArgTest) method exists so that you can override it and set a fixture up before, and clean it up after, each test. Thus, the previous temp file example could also be implemented without mixing in BeforeAndAfterEach, like this:

 import org.scalatest.FunSuite
 import org.scalatest.BeforeAndAfterEach
 import java.io.FileReader
 import java.io.FileWriter
 import java.io.File

 class MySuite extends FunSuite {

   private var reader: FileReader = _

   override def withFixture(test: NoArgTest) {

     val FileName = "TempFile.txt"

     // Set up the temp file needed by the test
     val writer = new FileWriter(FileName)
     try {
       writer.write("Hello, test!")
     }
     finally {
       writer.close()
     }

     // Create the reader needed by the test
     reader = new FileReader(FileName)

     try {
       test() // Invoke the test function
     }
     finally {
       // Close and delete the temp file
       reader.close()
       val file = new File(FileName)
       file.delete()
     }
   }

   test("reading from the temp file") {
     var builder = new StringBuilder
     var c = reader.read()
     while (c != -1) {
       builder.append(c.toChar)
       c = reader.read()
     }
     assert(builder.toString === "Hello, test!")
   }

   test("first char of the temp file") {
     assert(reader.read() === 'H')
   }
 
   test("without a fixture") {
     assert(1 + 1 === 2)
   }
 }
 

If you prefer to keep your test classes immutable, one final variation is to use the FixtureFunSuite trait from the org.scalatest.fixture package. Tests in an org.scalatest.fixture.FixtureFunSuite can have a fixture object passed in as a parameter. You must indicate the type of the fixture object by defining the Fixture type member and define a withFixture method that takes a one-arg test function. (A FixtureFunSuite has two overloaded withFixture methods, therefore, one that takes a OneArgTest and the other, inherited from Suite, that takes a NoArgTest.) Inside the withFixture(OneArgTest) method, you create the fixture, pass it into the test function, then perform any necessary cleanup after the test function returns. Instead of invoking each test directly, a FixtureFunSuite will pass a function that invokes the code of a test to withFixture(OneArgTest). Your withFixture(OneArgTest) method, therefore, is responsible for actually running the code of the test by invoking the test function. For example, you could pass the temp file reader fixture to each test that needs it by overriding the withFixture(OneArgTest) method of a FixtureFunSuite, like this:

 import org.scalatest.fixture.FixtureFunSuite
 import java.io.FileReader
 import java.io.FileWriter
 import java.io.File
 
 class MySuite extends FixtureFunSuite {

   type FixtureParam = FileReader

   def withFixture(test: OneArgTest) {

     val FileName = "TempFile.txt"

     // Set up the temp file needed by the test
     val writer = new FileWriter(FileName)
     try {
       writer.write("Hello, test!")
     }
     finally {
       writer.close()
     }

     // Create the reader needed by the test
     val reader = new FileReader(FileName)
  
     try {
       // Run the test using the temp file
       test(reader)
     }
     finally {
       // Close and delete the temp file
       reader.close()
       val file = new File(FileName)
       file.delete()
     }
   }
 
   test("reading from the temp file") { reader =>
     var builder = new StringBuilder
     var c = reader.read()
     while (c != -1) {
       builder.append(c.toChar)
       c = reader.read()
     }
     assert(builder.toString === "Hello, test!")
   }
 
   test("first char of the temp file") { reader =>
     assert(reader.read() === 'H')
   }
 
   test("without a fixture") { () => 
     assert(1 + 1 === 2)
   }
 }
 

It is worth noting that the only difference in the test code between the mutable BeforeAndAfterEach approach shown here and the immutable FixtureFunSuite approach shown previously is that two of the FixtureFunSuite's test functions take a FileReader as a parameter via the "reader =>" at the beginning of the function. Otherwise the test code is identical. One benefit of the explicit parameter is that, as demonstrated by the "without a fixture" test, a FixtureFunSuite test need not take the fixture. So you can have some tests that take a fixture, and others that don't. In this case, the FixtureFunSuite provides documentation indicating which tests use the fixture and which don't, whereas the BeforeAndAfterEach approach does not. (If you have want to combine tests that take different fixture types in the same FunSuite, you can use MultipleFixtureFunSuite.)

If you want to execute code before and after all tests (and nested suites) in a suite, such want to execute code before and after all tests (and nested suites) in a suite, such as you could do with @BeforeClass and @AfterClass annotations in JUnit 4, you can use the beforeAll and afterAll methods of BeforeAndAfterAll. See the documentation for BeforeAndAfterAll for an example.

Shared tests

Sometimes you may want to run the same test code on different fixture objects. In other words, you may want to write tests that are "shared" by different fixture objects. To accomplish this in a FunSuite, you first place shared tests in behavior functions. These behavior functions will be invoked during the construction phase of any FunSuite that uses them, so that the tests they contain will be registered as tests in that FunSuite. For example, given this stack class:

 import scala.collection.mutable.ListBuffer
 
 class Stack[T] {

   val MAX = 10
   private var buf = new ListBuffer[T]

   def push(o: T) {
     if (!full)
       o +: buf
     else
       throw new IllegalStateException("can't push onto a full stack")
   }

   def pop(): T = {
     if (!empty)
       buf.remove(0)
     else
       throw new IllegalStateException("can't pop an empty stack")
   }

   def peek: T = {
     if (!empty)
       buf(0)
     else
       throw new IllegalStateException("can't pop an empty stack")
   }

   def full: Boolean = buf.size == MAX
   def empty: Boolean = buf.size == 0
   def size = buf.size

   override def toString = buf.mkString("Stack(", ", ", ")")
 }
 

You may want to test the Stack class in different states: empty, full, with one item, with one item less than capacity, etc. You may find you have several tests that make sense any time the stack is non-empty. Thus you'd ideally want to run those same tests for three stack fixture objects: a full stack, a stack with a one item, and a stack with one item less than capacity. With shared tests, you can factor these tests out into a behavior function, into which you pass the stack fixture to use when running the tests. So in your FunSuite for stack, you'd invoke the behavior function three times, passing in each of the three stack fixtures so that the shared tests are run for all three fixtures.

You can define a behavior function that encapsulates these shared tests inside the FunSuite that uses them. If they are shared between different FunSuites, however, you could also define them in a separate trait that is mixed into each FunSuite that uses them. For example, here the nonEmptyStack behavior function (in this case, a behavior method) is defined in a trait along with another method containing shared tests for non-full stacks:

 import org.scalatest.FunSuite
 
 trait FunSuiteStackBehaviors { this: FunSuite =>
 
   def nonEmptyStack(createNonEmptyStack: => Stack[Int], lastItemAdded: Int) {
 
     test("empty is invoked on this non-empty stack: " + createNonEmptyStack.toString) {
       val stack = createNonEmptyStack
       assert(!stack.empty)
     }
 
     test("peek is invoked on this non-empty stack: " + createNonEmptyStack.toString) {
       val stack = createNonEmptyStack
       val size = stack.size
       assert(stack.peek === lastItemAdded)
       assert(stack.size === size)
     }
 
     test("pop is invoked on this non-empty stack: " + createNonEmptyStack.toString) {
       val stack = createNonEmptyStack
       val size = stack.size
       assert(stack.pop === lastItemAdded)
       assert(stack.size === size - 1)
     }
   }
   
   def nonFullStack(createNonFullStack: => Stack[Int]) {
       
     test("full is invoked on this non-full stack: " + createNonFullStack.toString) {
       val stack = createNonFullStack
       assert(!stack.full)
     }
       
     test("push is invoked on this non-full stack: " + createNonFullStack.toString) {
       val stack = createNonFullStack
       val size = stack.size
       stack.push(7)
       assert(stack.size === size + 1)
       assert(stack.peek === 7)
     }
   }
 }
 

Given these behavior functions, you could invoke them directly, but FunSuite offers a DSL for the purpose, which looks like this:

 testsFor(nonEmptyStack(stackWithOneItem, lastValuePushed))
 testsFor(nonFullStack(stackWithOneItem))
 

If you prefer to use an imperative style to change fixtures, for example by mixing in BeforeAndAfterEach and reassigning a stack var in beforeEach, you could write your behavior functions in the context of that var, which means you wouldn't need to pass in the stack fixture because it would be in scope already inside the behavior function. In that case, your code would look like this:

 testsFor(nonEmptyStack) // assuming lastValuePushed is also in scope inside nonEmptyStack
 testsFor(nonFullStack)
 

The recommended style, however, is the functional, pass-all-the-needed-values-in style. Here's an example:

 import org.scalatest.FunSuite
 
 class StackFunSuite extends FunSuite with FunSuiteStackBehaviors {
 
   // Stack fixture creation methods
   def emptyStack = new Stack[Int]
  
   def fullStack = {
     val stack = new Stack[Int]
     for (i <- 0 until stack.MAX)
       stack.push(i)
     stack
   }
  
   def stackWithOneItem = {
     val stack = new Stack[Int]
     stack.push(9)
     stack
   }
  
   def stackWithOneItemLessThanCapacity = {
     val stack = new Stack[Int]
     for (i <- 1 to 9)
       stack.push(i)
     stack
   }
  
   val lastValuePushed = 9
  
   test("empty is invoked on an empty stack") {
     val stack = emptyStack
     assert(stack.empty)
   }

   test("peek is invoked on an empty stack") {
     val stack = emptyStack
     intercept[IllegalStateException] {
       stack.peek
     }
   }

   test("pop is invoked on an empty stack") {
     val stack = emptyStack
     intercept[IllegalStateException] {
       emptyStack.pop
     }
   }

   testsFor(nonEmptyStack(stackWithOneItem, lastValuePushed))
   testsFor(nonFullStack(stackWithOneItem))

   testsFor(nonEmptyStack(stackWithOneItemLessThanCapacity, lastValuePushed))
   testsFor(nonFullStack(stackWithOneItemLessThanCapacity))

   test("full is invoked on a full stack") {
     val stack = fullStack
     assert(stack.full)
   }

   testsFor(nonEmptyStack(fullStack, lastValuePushed))

   test("push is invoked on a full stack") {
     val stack = fullStack
     intercept[IllegalStateException] {
       stack.push(10)
     }
   }
 }
 

If you load these classes into the Scala interpreter (with scalatest's JAR file on the class path), and execute it, you'll see:

 scala> (new StackFunSuite).execute()
 Test Starting - StackFunSuite: empty is invoked on an empty stack
 Test Succeeded - StackFunSuite: empty is invoked on an empty stack
 Test Starting - StackFunSuite: peek is invoked on an empty stack
 Test Succeeded - StackFunSuite: peek is invoked on an empty stack
 Test Starting - StackFunSuite: pop is invoked on an empty stack
 Test Succeeded - StackFunSuite: pop is invoked on an empty stack
 Test Starting - StackFunSuite: empty is invoked on this non-empty stack: Stack(9)
 Test Succeeded - StackFunSuite: empty is invoked on this non-empty stack: Stack(9)
 Test Starting - StackFunSuite: peek is invoked on this non-empty stack: Stack(9)
 Test Succeeded - StackFunSuite: peek is invoked on this non-empty stack: Stack(9)
 Test Starting - StackFunSuite: pop is invoked on this non-empty stack: Stack(9)
 Test Succeeded - StackFunSuite: pop is invoked on this non-empty stack: Stack(9)
 Test Starting - StackFunSuite: full is invoked on this non-full stack: Stack(9)
 Test Succeeded - StackFunSuite: full is invoked on this non-full stack: Stack(9)
 Test Starting - StackFunSuite: push is invoked on this non-full stack: Stack(9)
 Test Succeeded - StackFunSuite: push is invoked on this non-full stack: Stack(9)
 Test Starting - StackFunSuite: empty is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Succeeded - StackFunSuite: empty is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Starting - StackFunSuite: peek is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Succeeded - StackFunSuite: peek is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Starting - StackFunSuite: pop is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Succeeded - StackFunSuite: pop is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Starting - StackFunSuite: full is invoked on this non-full stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Succeeded - StackFunSuite: full is invoked on this non-full stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Starting - StackFunSuite: push is invoked on this non-full stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Succeeded - StackFunSuite: push is invoked on this non-full stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 Test Starting - StackFunSuite: full is invoked on a full stack
 Test Succeeded - StackFunSuite: full is invoked on a full stack
 Test Starting - StackFunSuite: empty is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 Test Succeeded - StackFunSuite: empty is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 Test Starting - StackFunSuite: peek is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 Test Succeeded - StackFunSuite: peek is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 Test Starting - StackFunSuite: pop is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 Test Succeeded - StackFunSuite: pop is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 Test Starting - StackFunSuite: push is invoked on a full stack
 Test Succeeded - StackFunSuite: push is invoked on a full stack
 

One thing to keep in mind when using shared tests is that in ScalaTest, each test in a suite must have a unique name. If you register the same tests repeatedly in the same suite, one problem you may encounter is an exception at runtime complaining that multiple tests are being registered with the same test name. In a FunSuite there is no nesting construct analogous to Spec's describe clause. Therefore, you need to do a bit of extra work to ensure that the test names are unique. If a duplicate test name problem shows up in a FunSuite, you'll need to pass in a prefix or suffix string to add to each test name. You can pass this string the same way you pass any other data needed by the shared tests, or just call toString on the shared fixture object. This is the approach taken by the previous FunSuiteStackBehaviors example.

Given this FunSuiteStackBehaviors trait, calling it with the stackWithOneItem fixture, like this:

 testsFor(nonEmptyStack(stackWithOneItem, lastValuePushed))
 

yields test names:

• empty is invoked on this non-empty stack: Stack(9)
• peek is invoked on this non-empty stack: Stack(9)
• pop is invoked on this non-empty stack: Stack(9)

Whereas calling it with the stackWithOneItemLessThanCapacity fixture, like this:

 testsFor(nonEmptyStack(stackWithOneItemLessThanCapacity, lastValuePushed))
 

yields different test names:

• empty is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
• peek is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
• pop is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)

Tagging tests

A FunSuite's tests may be classified into groups by tagging them with string names. As with any suite, when executing a FunSuite, groups of tests can optionally be included and/or excluded. To tag a FunSuite's tests, you pass objects that extend abstract class org.scalatest.Tag to methods that register tests, test and ignore. Class Tag takes one parameter, a string name. If you have created Java annotation interfaces for use as group names in direct subclasses of org.scalatest.Suite, then you will probably want to use group names on your FunSuites that match. To do so, simply pass the fully qualified names of the Java interfaces to the Tag constructor. For example, if you've defined Java annotation interfaces with fully qualified names, com.mycompany.groups.SlowTest and com.mycompany.groups.DbTest, then you could create matching groups for FunSuites like this:

 import org.scalatest.Tag

 object SlowTest extends Tag("com.mycompany.groups.SlowTest")
 object DbTest extends Tag("com.mycompany.groups.DbTest")
 

Given these definitions, you could place FunSuite tests into groups like this:

 import org.scalatest.FunSuite

 class MySuite extends FunSuite {

   test("addition", SlowTest) {
     val sum = 1 + 1
     assert(sum === 2)
     assert(sum + 2 === 4)
   }

   test("subtraction", SlowTest, DbTest) {
     val diff = 4 - 1
     assert(diff === 3)
     assert(diff - 2 === 1)
   }
 }
 

This code marks both tests, "addition" and "subtraction," with the com.mycompany.groups.SlowTest tag, and test "subtraction" with the com.mycompany.groups.DbTest tag.

The primary run method takes a Filter, whose constructor takes an optional Set[String]s called tagsToInclude and a Set[String] called tagsToExclude. If tagsToInclude is None, all tests will be run except those those belonging to tags listed in the tagsToExclude Set. If tagsToInclude is defined, only tests belonging to tags mentioned in the tagsToInclude set, and not mentioned in tagsToExclude, will be run.

Ignored tests

To support the common use case of “temporarily” disabling a test, with the good intention of resurrecting the test at a later time, FunSuite provides registration methods that start with ignore instead of test. For example, to temporarily disable the test named addition, just change “test” into “ignore,” like this:

 import org.scalatest.FunSuite

 class MySuite extends FunSuite {

   ignore("addition") {
     val sum = 1 + 1
     assert(sum === 2)
     assert(sum + 2 === 4)
   }

   test("subtraction") {
     val diff = 4 - 1
     assert(diff === 3)
     assert(diff - 2 === 1)
   }
 }
 

If you run this version of MySuite with:

 scala> (new MySuite).execute()
 

It will run only subtraction and report that addition was ignored:

 Test Ignored - MySuite: addition
 Test Starting - MySuite: subtraction
 Test Succeeded - MySuite: subtraction
 

Pending tests

A pending test is one that has been given a name but is not yet implemented. The purpose of pending tests is to facilitate a style of testing in which documentation of behavior is sketched out before tests are written to verify that behavior (and often, the before the behavior of the system being tested is itself implemented). Such sketches form a kind of specification of what tests and functionality to implement later.

To support this style of testing, a test can be given a name that specifies one bit of behavior required by the system being tested. The test can also include some code that sends more information about the behavior to the reporter when the tests run. At the end of the test, it can call method pending, which will cause it to complete abruptly with TestPendingException. Because tests in ScalaTest can be designated as pending with TestPendingException, both the test name and any information sent to the reporter when running the test can appear in the report of a test run. (In other words, the code of a pending test is executed just like any other test.) However, because the test completes abruptly with TestPendingException, the test will be reported as pending, to indicate the actual test, and possibly the functionality, has not yet been implemented.

Although pending tests may be used more often in specification-style suites, such as org.scalatest.Spec, you can also use it in FunSuite, like this:

 import org.scalatest.FunSuite

 class MySuite extends FunSuite {

   def test("addition") {
     val sum = 1 + 1
     assert(sum === 2)
     assert(sum + 2 === 4)
   }

   def test("subtraction") (pending)
 }
 

(Note: "(pending)" is the body of the test. Thus the test contains just one statement, an invocation of the pending method, which throws TestPendingException.) If you run this version of MySuite with:

 scala> (new MySuite).execute()
 

It will run both tests, but report that subtraction is pending. You'll see:

 Test Starting - MySuite: addition
 Test Succeeded - MySuite: addition
 Test Starting - MySuite: subtraction
 Test Pending - MySuite: subtraction
 

Informers

One of the parameters to the primary run method is a Reporter, which will collect and report information about the running suite of tests. Information about suites and tests that were run, whether tests succeeded or failed, and tests that were ignored will be passed to the Reporter as the suite runs. Most often the reporting done by default by FunSuite's methods will be sufficient, but occasionally you may wish to provide custom information to the Reporter from a test. For this purpose, an Informer that will forward information to the current Reporter is provided via the info parameterless method. You can pass the extra information to the Informer via one of its apply methods. The Informer will then pass the information to the Reporter via an InfoProvided event. Here's an example:

 import org.scalatest.FunSuite

 class MySuite extends FunSuite {

   test("addition") {
     val sum = 1 + 1
     assert(sum === 2)
     assert(sum + 2 === 4)
     info("Addition seems to work")
   }
 }
 

 Test Starting - MySuite: addition
 Info Provided - MySuite.addition: Addition seems to work
 Test Succeeded - MySuite: addition